Fluorocarbon phosphorus rings



FLUOROCARBON PHOSPHORUS RING Anton B. Burg and Walter Mahler, LosAngeles, Calif., assignors, by mesne assignments, to American Potash &Chemical Corporation, a corporation of Delaware No Drawing. ApplicationDecember 30, 1957 Serial No. 705,814

Claims. (Cl. 260-6065) This invention relates in general to thepreparation of fluorocarbon phosphorus compounds through the thermaldecomposition of fluorocarbon phosphines. More particularly, thisinvention relates to a method for the preparation of polymers of PCFunits through the thermal decomp osiuonor' such compounds as P tCP and(CF PH.

It is an object of this invention to provide a method whereby certainbasically inorganic polymers may be formed.

A further object of this invention is to provide a method whereby,through the thermal decomposition of certain precursors, compounds maybe prepared which have a plurality. of phosphorus atoms joined one tothe next and fluorocarbon groups bonded to each of the phosphorus atoms.

Ancillary objects and advantages of this invention, if not specificallyset forth, will become apparent during the course of the discussionwhich follows.

Generally, it has been found that on pyrolyzing the fluorocarbonphosphincs at temperatures preferably in the neighborhood of 300-3S0 C.,stable compounds form which are phosphorus ring compounds having thegeneral formula (PCF More particularly, it has been found that thedesired phosphorus ring compounds as set forth in our copendingapplication Serial No. 705,831, filed even date herewith, may be formedby pyrolyzing compounds of the type P (CF and (CF Pl-l at temperatureswithin the range 300-350 C. Higher temperatures encourage decompositionof the desired reaction products, while lower temperatures yield theproducts, but at reduced rates. Preferably, apparatus is employedpermitting condensation of the desired PCF groups or newly formedpolymers and their immediate removal from the high temperature zone.Decomposition of the product is thereby avoided.

The method of the aforementioned copending application wherein the (CFP) and (CF P) were analyzed by their reaction with iodine whichquantitatively reverted the products to 4 or 5 moles of CF PI was usedto aid in identifying the products here. These in turn were converteddirectly to HCF by alkaline hydrolysis. The direct alkaline hydrolysisof the CF polymers delivered only half of the CF, groups as HCF whilethe others were partIy broken down. Such behavior is consistent with theresults of alkaline hydrolysis of (CF PH and P (CF The vapor density ofthe tetramer was such as to give the molecular Weight of 402, ascompared with a calculated 400. In similar fashion the vapor density ofthe pentamer was determined and'its molecularqweight indication closelycorresponded with that of the calculated, 495 as against the calculated500.

Various examples are set forth below for illustrative purposes but arenot to be construed as placing limitations on the scope of the inventionother than as are set forth in the appended claims.

Example 1 In the pyrolysis of P (CF a 4 m. mole sample of P (CF washeated in one leg of a pyrolysis chamber. The products were removed fromthe reaction zone by means of a 0 condenser, 4 m. moles of (CF P wereproduced along with 0.33 m. mole of (PCF a 33% yield, and 0.05 m. moleof (PCF a 6% yield. The remainder consisted of higher (PCF polymers.

Example 2 In another experiment run in the fashion of that set forth butat a somewhat lesser tern; :rature, 300 C., in the presence ofborontrifiuoride, the yield of (PCF was 50% of that demanded by theequation:

The borontrifiuoride used here was probably ineffective as about of itwas recovered thereafter.

Example 3 The polymers (PCB-Q and (PCF Were obtained and were nextseparated in accordance with the procedures set forth in the alreadymentioned copending application. Lesser amounts of higher polymers werepresent in the reaction mixture.

As set forth in our copending application Serial No. 705,831 forFluorocarbon Phosphorus Rings, the products prepared according to theprocess of this invention find utility as antioxidants soluble inhydrocarbons. Further, they may be oxidized to polymeric materials ofthe general formula (CF PO the more volatile components of which may bedriven 01f to leave a solid polymeric material which acts as anexcellent water scavenger and yet is resistant to oxidation. Also, thismaterial is stable at fairly high temperatures and hence findsparticular utility in high temperature applications.

As set forth in the copending application above-mentioned, the PCFpolymers find other uses as incendiary igniters, and as additives forlubricants and hydraulic fluids for the prevention of damage due to theaction of ionizing radiation.

Obviously many modifications and variations of this 7 f Patented, Feb. 21960} This product was heated at v.

The reaction thus proceeded acinvention may be made without departingfrom the spirit and scope thereof and therefore only such limitationsshould be imposed as are indicated in the appended Claims.

We claim:

1. A process for preparing a chemical composition having the formula(PCF wherein x is an integer greater than 3 and wherein the phosphorusatJms are arranged in a ring structure which comprises: pyrolyzing afluorocarbon phosphine whereby to yield units of CF P.

groups and allowing said CF 1 groups to thereafter arrange themselvesinto ring structures corresponding tos aid formula. (PCFgl- 2. Theproces: of claim- 1, wherein the pyrolyzing temperatures are about 300to 350 C.

3. The process of claim 1, wherein the fluorocarbon phosphine is P (CF4. The process of claim 1, wherein the fluorocarbon phosphine is (CF PH.v

5. The process of claim 1, wherein the CF P groups formed by pyrolysisare immediately thereafter condensed and removed from the heatedreaction zone.

No references cited.

1. A PROCESS FOR PREPARING A CHEMICAL COMPOSITION HAVING THE FORMULA (PCF3)I WHEREIN X IS AN INTEGER GREATER THAN 3 AND WHEREIN THE PHOSPHOROUS ATOMS ARE ARRANGED IN A RING STRUCTURE WHICH COMPRISES: PYROLYZING A FLUOROCARBON PHOSPHINE WHEREBY TO YIELD UNITS OF CF3P GROUPS AND ALLOWING SAID CF3P GROUPS TO THEREAFTER ARRANGE THEMSELVES INTO RING STRUCTURES CORRESPONDING TO SAID FORMULA (PCF3)X. 